Mysterious Worms

[Kirrashi]

Hello! I have attempted to read every relevant thread and linked article, but I am still at a loss as to what this critter is and what to do about it.

Tank is new, contains plants, bladder snails, and 4 magenta mystery snails.  2 attempts to add neocaridina shrimp have resulted in all shrimp dead or missing within 1 week or less.  We noticed these little worms on the glass around the same time that we noticed the first bladder snails (arrived with plants).  We thought we had identified them as a harmless flatworm, but talking about the shrimp deaths at our LFS reopened the can of worms, as it were.  Particularly the one that completely vanished.  They said it "did not look like a harmless detritus worm" and recommended we use "Aquatic Remedies Planaria Stop" on the theory that it is some kind of worm that "is a harmless parasite, until there are so many that the breathing of the host is obstructed". We haven't been able to figure out what kind of worm that actually would be, as I can't remember the name they used. 

Anyway, now we are terrified that our only success so far- these beautiful snails- is going to disappear.  Planaria treatments all seem to be bad for snails. The Mystery snails we can find and remove, but not all the little bladder snails we've come to love too. (Yes, we get attached to everything.)  Another factor is that we don't actually have a quarantine setup, since we haven't even got as far as purchasing fish yet.

I am planning to do a late-night check for anything that might be moving about when it's dark that we haven't seen yet.

tank parameters: 20g long, 75F, seachem 55 filter on a low flow setting, ph 7.2ish,  gh 8, nitrite 0, ammonia 0, nitrate 10ish.  added one additional hour of lights-on time a week ago for viewing convenience.

What does this critter look like to you? How worried should I be about sudden snail death?

[Melkor]

Rhabdocoela

[Anjum]

It does look like a Planaria unfortunately, or a related flatworm that has a more rounded head. And you are correct, the medications that will kill planaria may harm your snails. It's possible if you get fish in there soon enough, they will eat the worms & your problem will be solved. What kind of fish were you planning on adding? 

On 6/14/2022 at 4:12 PM, Melkor said:

Rhabdocoela

That's the one!

[Solstice_Lacer]

I agree it looks like rhabdocelea, but I'm not sure they are dangerous to living creatures. Have you seen them on any of the snails? When you say the tank is new, how new? Where did you get your shrimp from? It does not look like the harmful planaria I'm (unfortunately) familiar with. I wouldn't resort to planaria meds just yet if you're worried about snails.

[Guppysnail]

Rhabdocoela are not harmful. They feed on biofilm and micro algae.  I pulled a picture from the internet to help you see the difference in those and planaria. Anything that will harm flatworms will harm snails as their body is similar in structure and tissue. Yours looks like a common rhabdocoela so no worries. I get them in snail only tanks and have not lost snails

[Kirrashi]

Thank you! Yes, Rhabdocoela is what we though it was, until we were told otherwise.  Glad to have more votes in this favor!

On 6/14/2022 at 7:58 PM, Solstice_Lacer said:

I agree it looks like rhabdocelea, but I'm not sure they are dangerous to living creatures. Have you seen them on any of the snails? When you say the tank is new, how new? Where did you get your shrimp from? It does not look like the harmful planaria I'm (unfortunately) familiar with. I wouldn't resort to planaria meds just yet if you're worried about snails.

Tank started in March. I haven't seen any of them on the snails, though we have seen the snails run into them, and the comparatively giant snail will recoil and change direction.  The shrimp were from an online aquatics store, so I understand it may have been international shipping stress as much as any other reason. (I think I am not supposed to discus specific vendors per forum rules, correct?) The snails were from the same shop.

On 6/14/2022 at 7:12 PM, Anjum said:

It does look like a Planaria unfortunately, or a related flatworm that has a more rounded head. And you are correct, the medications that will kill planaria may harm your snails. It's possible if you get fish in there soon enough, they will eat the worms & your problem will be solved. What kind of fish were you planning on adding? 

That's the one!

One of the very small rasboras or danios will probably be first.  Kubotai rasboras and gold ring danios are my current top choices.

[Solstice_Lacer]

The shrimp dying could be stress or bad luck. Or they may have had molting issues. If you try shrimp again, see if you can find them local if possible. If that's not an option maybe try looking for a dedicated shrimp breeder, and check how far away they'll be shipping. Also ask for water parameters if possible.

Add a piece of cuttle bone to help shells/molts. An almond leaf and a piece of wood if you don't already have one. Shrimp love to graze on both. They are neat little critters so I'm sorry you haven't had good experiences with them.

(Also I love the look of gold ring danios, but I haven't been able to find them.)

 

[BigJ]

I had my shrimp shipped from a dedicated breeder who I thought was local. Then according to the return address they were only about an hour away, I attribute part of my success to that.

[Anjum]

On 6/14/2022 at 6:08 PM, Kirrashi said:

One of the very small rasboras or danios will probably be first.  Kubotai rasboras and gold ring danios are my current top choices.

Most rasboras & danios will eat the worms if they're small enough. 

[Kirrashi]

On 6/14/2022 at 10:31 PM, BigJ said:

I had my shrimp shipped from a dedicated breeder who I thought was local. Then according to the return address they were only about an hour away, I attribute part of my success to that.

You wouldn't happen to be in New England by chance?

 

On 6/14/2022 at 10:10 PM, Solstice_Lacer said:

The shrimp dying could be stress or bad luck. Or they may have had molting issues. If you try shrimp again, see if you can find them local if possible. If that's not an option maybe try looking for a dedicated shrimp breeder, and check how far away they'll be shipping. Also ask for water parameters if possible.

Add a piece of cuttle bone to help shells/molts. An almond leaf and a piece of wood if you don't already have one. Shrimp love to graze on both. They are neat little critters so I'm sorry you haven't had good experiences with them.

(Also I love the look of gold ring danios, but I haven't been able to find them.)

 

At least some of the shrimp in the first attempt did seem to have molting issues. Two (one from each attempt) successfully molted, but died about 48 hours later. We removed the molts in case of parasite eggs. (One shrimp may have had Scutariella Japonica.) 

We are using Salty Shrimp to make sure our water changes keep the hardness we are aiming for, and have distilled water to top off in case of creeping. There is a big piece of wood that the shrimp did like while they were seeming healthy.

One thing we noticed was that maybe 12-20ish hours before death/disappearance the shrimps would get very very active- zooming around the tank, only momentarily pausing to nibble, then zooming some more. They would also bump into the glass while doing this. We thought this meant the shrimp was feeling safe and exploring, then were really shocked when they were dead.  I think now that this must have been somehow evident of the shrimp being in distress.

About the Gold ring Danios- I don't think I've seen then actually listed as "in stock" more than once in the last couple months of fish-browsing. I definitely would prefer to get non-international tank-bred fish than wild caught ones if it's possible, and I'm not sure that's an option yet for them.

[BigJ]

On 6/16/2022 at 12:58 PM, Kirrashi said:

You wouldn't happen to be in New England by chance?

No, Texas sorry.